Analysis of the evaporator of the absorption refrigerating secondary condensation unit of ammonia production was performed. The need to minimize the temperature mode of operation of the evaporator, which provides for energy efficiency in ammonia production by decreasing natural gas consumption was substantiated. Statistical processing of experimental data with assessment of the quality of obtained information was performed. Identification of the heat exchange process of the evaporator was performed and the equation for numerical evaluation of uncertainty of coefficients of thermal efficiency, heat transfer and condensation thermal resistance was obtained. According to the results of statistical modeling of the primary condensation unit, the equation for numerical evaluation of uncertainty of ammonia concentration in circulating gas at the evaporator inlet. The authors proved the possibility of its application for identification and mathematical modeling of heat exchange process at existing relationship of ammonia concentration in the circulating gas at the evaporator inlet and condensation thermal resistance. Algorithmic support of numerical evaluation of uncertainties and calculation of target indicators of the evaporator’s efficiency was created. The technical structure of the automated system for identification and timely obtaining of the mathematical model of the evaporator, which is adapted to the existing information system of the industrial ammonia synthesis unit, was developed.